‘This multimillion-pound contract shows our commitment to investing in new ships for the Royal Navy and maintaining in the UK the expertise needed to build the warships of the future.

‘It will benefit the dedicated workers of the Clyde, their families and the local economy in Glasgow.

‘This sort of investment by the UK government is vital for the sustainment of shipbuilding in the city and the hundreds of specialist manufacturing and engineering roles that play an important role in providing war fighting capability.’

Shipyard workers at BAE in Portsmouth have built three Brazilian ocean patrol vessels as part of a £133m deal.

The decision to axe shipbuilding in Portsmouth was announced last year, with 900 jobs lost in the city.

But Mr Fallon previously said that contracts would need to be revisited if Scotland voted for independence.

During a visit to the city’s Highbury College in June he said: ‘I hope Scotland won’t vote for independence but if they did there are an awful lot of contracts that would need to be revisited.’

The new 90-metre OPVs will be built at BAE’s facilities in Glasgow and will be used in a variety of roles.